Light & Eye

Question 1

What is light?

Answer 1

Electromagnetic radiation

Question 2

What is the range of visible light?

Answer 2

400 nm - 700 nm

Question 3

What are 7 ways light can interact with materials?

Answer 3

Reflect
Absorb (transduction/emmission)
Refraction
Diffraction
Scattering
Transmission
Polarization

Question 4

What is Rayleigh Scattering?

Answer 4

The scattering of indirect sunlight in air, appearing blue

Question 5

What is Mie Scattering?

Answer 5

The scattering of direct sunlight in air, appearing white

Question 6

Why do sunsets/sunrises appear red?

Answer 6

There is more atmosphere for the light to travel through, more of the short wavelengths get scattered

Question 7

What are 3 types of polarization?

Answer 7

Scattering
Absorption
Reflection

Question 8

How do anti road glare glasses work?

Answer 8

Sunlight reflecting off the road is approximately horizontally polarized as it reaches your eyes
The glasses are polarized vertically, such that it minimizes (but not completely) the glare

Question 9

What causes refraction?

Answer 9

The change in apparent speeds of light in material

Question 10

Concave lenses ____ light from its optic axis whereas Convex lenses ____ light from its optic axis

Answer 10

Diverge

Converge

Question 11

Plano(concave/vex) lenses have (the same/different) properties as fully (concave/vex) lenses and this effect (is/isn’t) orientation sensitive

Answer 11

The same

isn’t

Question 12

If the bulge of a planoconvex lens increases, what happens to its focal point?

Answer 12

Moves closer to the lens

Question 13

If the indentation of a planoconcave lens becomes more curved, what happens to the light rays?

Answer 13

They diverge more

Question 14

If you move an object closer to a convex lens, what happens to its image? How would you change the lens to correct this?

Answer 14

It gets farther from the lens

Bulge the lens more

Question 15

Define the following
Pupil
Cornea
Iris
Lens
Sclera
Retina
Fovea

Answer 15

Pupil: hole in eye
Cornea: outer layer of eye
Iris: controls pupil size
Lens: lens
Sclera: white of eye
Retina: Receptor area of eye
Fovea: spot on macula of eye

Question 16

What are the 6 eye muscles and what do they do?

Answer 16

Superior/inferior rectus: up/down
Medial/lateral rectus: left/right
Superior/inferior oblique: (anti)clockwise

Question 17

True/False? The human eye is perfect, and that is why it is the main argument for intelligent design

Answer 17

False

Question 18

What is the average field of view? What is the range of steroscopic view?

Answer 18

190 degrees, 110 degrees

Question 19

When an image passes through the lens, is it flipped left/right or upside down?

Answer 19

Both

Question 20

What components of the eye refract light?

Answer 20

Cornea and lens

Question 21

How do your eyes focus on an object?

Answer 21

Your crystalline lens contracts/relaxes

Question 22

If you move an object closer towards you, how do your eyes accommodate this change?

Answer 22

They bulge more

Question 23

What is accommodation?

Answer 23

The contraction/relaxation of the ciliary muscles (connected to the lens via zonule fibres) allowing the image to stay in focus

Question 24

How is presbyopia different from far sightedness?

Answer 24

It is related to aging

Question 25

What is myopia? How is it corrected?

Answer 25

Near-sightedness due to elongated eyeball, concave lenses

Question 26

What is hyperopia? How is it corrected?

Answer 26

Far-sightedness due to shortened eyeball, convex lenses